Weight
Training - Protecting
You Against Free Radical Damage
Aerobic exercise, including running, biking and walking, can strengthen
the heart and improve cardiovascular health in old age. Now, study
results suggest that another type of exercise--weightlifting--may
also protect the heart.

According to findings presented recently at the annual meeting of
the American College of Sports Medicine in Indianapolis, Indiana,
lifting weights--even light ones--can protect against free radial
damage. Free radicals are natural by-products of metabolism that
have been implicated in the aging process and in a number of chronic
illnesses such as heart disease and cancer.

The findings, said lead author Dr. Kevin Vincent of the University
of Florida at Gainesville, suggest that elderly people and those
who cannot lift heavy loads can still derive significant health
benefits from weightlifting.

"We
think this will open up the options for prescribing exercise to
seniors and other populations allowing them to use lighter loads
that are less likely to cause injury but can still provide the same
benefits," he noted in a statement.

The investigators found that healthy men and women aged 60 to 85
who performed a series of high- or low-intensity exercises with
weights three times a week had less damage from free radicals after
exertion, compared with a group of people who did not lift weights.

To measure free radical damage, the researchers looked at blood
levels of lipid peroxides, compounds resulting from the oxidation
of blood-borne fats that are thought to accumulate on the lining
of arteries, contributing to atherosclerosis, or "hardening of the
arteries."

After 6 months, the study participants were given an exercise test.
The free radical damage increased 13% in the post-exercise period
in the group that did not lift weights and decreased 2% in the low-intensity
weightlifting group. However, free radical damage increased slightly--2%--in
the high-intensity weightlifting group.

Vincent
explained that exercise can cause free radical damage because it
requires the body to use more oxygen. But exercise also enhances
the body's natural defense system, thereby protecting against free
radical damage, he said.

In other findings, people in the high-intensity group increased
their bone mass, thereby reducing their risk of the bone-thinning
disease osteoporosis, and lowered blood levels of homocysteine,
a substance that can increase the risk of heart disease.

Both the high- and low-intensity groups showed improvements in aerobic
fitness and increases in muscle strength and endurance after 6 months,
Vincent's team observed.

"These
findings suggest that resistance training in older adults may confer
additional metabolic benefits...which may reduce the potential for
chronic disease," said Barry Franklin, president of the American
College of Sports Medicine, in
a statement.